feat: non-destructive lock recovery for pushed branches (Closes #440)

Adds structured issue-branch ownership parsing, wires it into lock adoption
and gitea_lock_issue validation, documents the restart recovery workflow, and
adds regression tests for adoption, durable create_pr resolution, and open-PR
blocking without remote branch deletion.

Built on keyed persistent lock store and own-branch adoption (#443 / #442).

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

gitea_mcp_server.py

@@ -541,6 +541,7 @@ import issue_lock_worktree  # noqa: E402
 import issue_lock_provenance  # noqa: E402
 import issue_lock_store  # noqa: E402
 import issue_lock_adoption  # noqa: E402
+import issue_branch_ownership  # noqa: E402
 import already_landed_reconcile  # noqa: E402
 import author_mutation_worktree  # noqa: E402
 import issue_claim_heartbeat  # noqa: E402
@@ -1286,11 +1287,11 @@ def gitea_lock_issue(
         worktree_path: Author scratch-clone path to validate (defaults to
             GITEA_AUTHOR_WORKTREE or the MCP server project root).
     """
-    # 1. Enforce branch name includes issue number
-    expected_pattern = f"issue-{issue_number}"
-    if expected_pattern not in branch_name:
+    # 1. Enforce canonical issue branch ownership (#440)
+    if not issue_branch_ownership.branch_belongs_to_issue(branch_name, issue_number):
         raise ValueError(
-            f"Branch name '{branch_name}' must contain locked issue pattern '{expected_pattern}' (fail closed)"
+            f"Branch name '{branch_name}' must match "
+            f"(fix|feat|docs|chore)/issue-{issue_number}-<desc> (fail closed)"
         )
 
     blocked = _profile_permission_block(